There has been an increasing interest in β-amino acids and peptides derived from them, and, more particularly, in optically active β-amino acids and peptides derived from such optically active β-amino acids. Optically active β-amino acids include a number of naturally occurring substances in the free form with an interesting pharmacological profile. Functionalized β-amino acids are important segments of bioactive molecules. For example, TAXOL™ contains a phenylisoserine side chain as a key pharmacophore, and compounds of cyclic β-amino acids make up the class of β-lactam antibiotics. Additionally, β-amino acids are components of peptidic natural products with a wide range of biological activity. Peptides consisting of β-amino acids have promising pharmaceutical use as orally active drugs since they are hydrolytically stable. Given the significance of the β-amino acids, development of new methodologies for their synthesis, especially for the stereoselective synthesis of chiral β-amino acids, is important.
Accordingly, in view of the potential pharmaceutical utility of β-amino acids and βpeptides, there is a continuing need for methods for the preparation of β-amino acids, especially β-amino acids in optically active form, and the present invention is directed, in part, to addressing this need.